Kurland 1961.

Study characteristics
Methods	Type: clinical Design: parallel Objective: to determine differential effects of various phenothiazine derivatives on morbidity and severity of illness Treatment duration: 6 weeks Follow‐up duration (including treatment duration): 6 weeks Washout between cross‐over periods: NA
Data	Country: USA Condition: indication for tranquillisers, e.g. anxiety, agitation, restlessness Number of people randomised: 37 "referred" to active placebo and 37 to standard placebo (277 for all arms) Number of people analysed: 23 in active placebo group and 29 in standard placebo group with at least 1 assessment (at 2 weeks or later; 187 for all arms)
Comparisons	Active placebo: phenobarbital (IV: minimum daily dose 195 mg; oral: minimum daily dose 97.5 mg) Standard placebo: saline and lactose Experimental intervention: 6 arms with different phenothiazines (doses in brackets are minimum daily doses): promazine (IV: 150 mg; oral: 300 mg), chlorpromazine (IV: 75 mg; oral: 300 mg), mepazine (IV: 75 mg; oral: 75 mg), triflupromazine (IV: 75 mg; oral: 75 mg), prochlorperazine (IV: 15 mg; oral: 30 mg), and perphenazine (IV: 15 mg; oral: 24 mg) Administration: IV for the first 2 days, then oral
Outcomes	Participant‐reported outcome: none Observer‐reported outcome: Multidimensional Scale for Rating Psychiatric Patients (MSRPP) at the latest available assessment (2 weeks or later) Harm outcome: side effects causing termination of treatment Co‐intervention outcome: none
Terminology for active placebo	"Active placebo" a priori
Scores and unpleasantness of the active placebo	Adequacy: 2 Risk of therapeutic effect: 1 Unpleasant/neutral/pleasant: unpleasant
Funding and conflicts of interest	Funding unclear (funded by non‐commercial organisations, but several pharmaceutical companies are acknowledged). Conflicts of interest not reported.
Notes	SD for MSRPP scale imputed from other studies.
Risk of bias
Item	Authors' judgement	Support for judgement
Free from risk of bias arising from the randomisation process	Unclear	No information.
Free from risk of bias in selection of the reported result All outcomes	Unclear	Outcome probably not selected on the basis of results. No other information.